Primates

Gorillas Make New “Snough” Noise to Get Their Keepers’ Attention

Captive Gorillas Learn to Communicate with Humans

Years ago, Dr. Roberta Salmi, a biological anthropologist at Zoo Atlanta, noticed an unusual sound coming from the gorillas. When zookeepers approached with food, the gorillas would open their mouths wide and let out a theatrical noise between a cough and a sneeze—a “snough.”

At first, Salmi and the zookeepers were amused, but they soon realized that the snoughing was more than just a funny noise. It was a way for the gorillas to communicate with their human caretakers.

Zoo Gorillas Snough to Get Food

To study this behavior, Salmi and her colleagues conducted an experiment involving eight western lowland gorillas at Zoo Atlanta. They placed a bucket of grapes outside the animals’ enclosure, had a keeper stand outside the cage, and had the keeper hold a bucket of grapes.

The gorillas mostly stayed quiet when presented with just the grapes or just the keeper. However, they snoughed—and made other attention-grabbing noises and motions—when the keeper held the food.

Half of the gorillas snoughed during the experiment, and they kept making the noise until the zookeeper reacted. The gorillas never snoughed toward each other, which suggests that the sound is reserved for humans.

Snoughing Is a Rare Capability Among Animals

Scientists have never observed gorillas snoughing in the wild, which suggests that captive gorillas can learn to make new sounds. This is a rare capability among animals. Most animals are limited to the vocalizations they are born with, but some primates, including gorillas, chimpanzees, and orangutans, have shown the ability to learn new vocalizations in captivity.

Snoughing May Be a Form of Vocal Learning

The findings of Salmi’s study add to a growing body of evidence that suggests primates may have limited or moderate vocal learning abilities. Vocal learning is the ability to learn new vocalizations through imitation. Humans are the most proficient vocal learners, but some animals, such as birds and whales, also have this ability.

Other Apes Have Also Learned to Make New Sounds

Scientists have documented other apes in captivity learning to make new noises, including chimpanzees and orangutans. For example, some chimpanzees have learned to imitate human speech, and some orangutans have learned to make a variety of vocalizations, including whistles and clicks.

Snoughing Is a Way for Gorillas to Request Food

The researchers believe that gorillas started snoughing to get their keepers’ attention. They may have realized that sounds connected with illness got a response from the keepers, so they began to snough to request food.

Snoughing Is a Complex Behavior

Snoughing is a complex behavior that involves both vocal and physical components. The gorillas open their mouths wide, exhale forcefully, and sometimes make other noises and motions, such as clapping, beating their chests, and banging on the enclosure.

Snoughing Is a Social Behavior

Snoughing is a social behavior that is directed toward humans. Gorillas only snough toward zookeepers and other humans, not toward each other. This suggests that snoughing is a way for gorillas to communicate with humans.

Snoughing Is a Learned Behavior

Snoughing is a learned behavior that is not found in wild gorillas. This suggests that gorillas are capable of learning new vocalizations and behaviors in captivity.

Snoughing May Help Gorillas Cope with Captivity

Snoughing may help gorillas cope with the challenges of captivity. By learning to communicate with their human caretakers, gorillas can get their needs met and improve their well-being.